Former Wales and Cardiff Blues hooker Gareth Williams has retired on medical advice because of a neck injury.
The 31-year-old, who had surgery on his neck in 2010, injured it again during a pre-season friendly.
Williams could have another major operation but there is no guarantee it would be would be a success.
"The doctor said if I did come back playing I may be opening myself up to some permanent damage and there's no guarantee it would work," he said.
"His advice was to retire, so I'm hanging up my boots."
Williams, who won his first Wales cap against Italy in 2003, added: "I damaged some more discs in the neck close to where I had the operation, which are now fused together.
"If I were to have the operation, it would be quite a big procedure."
Former Wales Youth skipper Williams signed for Cardiff from Bridgend in the summer of 2003.
"I've enjoyed my time with the Blues," said Williams.
"I've been lucky enough to play with such amazing players and some great characters of the game. I couldn't have wished to be in a better side."